Fig. 2

Proliferative ability and cellular senescence of RA patient-derived SF-MSCs. a Comparison of SF-MSC proliferation by MTT assay. b Cell cycle status of SF-MSCs by flow cytometry. c The range of telomere restriction fragment (TRF) lengths (kb) in SF-MSCs by non-radioactive chemiluminescent assay. d Evaluation of the relative telomerase activity (RTA) in SF-MSCs by qRT-PCR. e Comparison of β-galactosidase-positive cell populations in SF-MSCs. 100× magnification. The asterisks indicate significant differences. The data represent mean values ± SD. N/C, negative control; P/C, positive control; SA β-gal, senescence-associated β-galactosidase; SASP, senescence associated secretory phenotype; MMPs, matrix metalloproteinases